Geoscience Australia is conducting a study under the National Carbon Infrastructure Plan (NCIP) to assess the suitability of the Vlaming Sub-basin for CO2 storage. It involves characterisation of the Valanginian reservoir (Gage Sandstone) and the Early Cretaceous seal (South Perth Shale) by integrating seismic interpretation and well log analysis in a detailed sequence stratigraphic investigation. The Gage Sandstone, comprised of channelised turbidites and mass flows, was the first unit deposited after breakup between India and Australia. Deposited during a sea level lowstand in the palaeo-topographic lows of the breakup unconformity, it is overlain by a thick deltaic to shallow marine succession of the South Perth Shale. The Gage Sandstone is considered one of the best reservoirs in the sub-basin with porosities of 23-30% and permeabilities of 200-1800 mD. It occurs at depths between 1000 and 3000 m below the seafloor, which makes, it an attractive target for the injection and long-term storage of supercritical CO2. The new extent of the Gage Sandstone, based on seismic interpretation and well log correlation, shows that in some of the wells the sandstone unit overlying the Valanginian unconformity belongs to the South Perth Shale and not to the Gage Sandstone. The G. Mutabilis palynological zone used in the past for identifying Gage Sandstone interval appears to be facies controlled and time transgressive. Detailed analysis of the reservoir properties at the wells in conjunction with systematic seismic facies mapping will serve as a basis for a regional reservoir model and storage potential estimation of the Gage Sandstone reservoir.

The Petrel Sub-basin Marine Environmental Survey GA-0335, (SOL5463) was undertaken using the RV Solander during May 2012 as part of the Commonwealth Government's National Low Emission Coal Initiative (NLECI). The survey was undertaken as a collaboration between the Australian Institute of Marine Science (AIMS) and GA. The purpose was to acquire geophysical and biophysical data on shallow (less then 100m water depth) seabed environments within two targeted areas in the Petrel Sub-basin to support investigation for CO2 storage potential in these areas. This 10 sample data-set comprises specific surface area and bulk (%) carbonate data from surface seabed sediments (~0-2 cm) in the Timor Sea.

Residual CO2 saturation (Sgr-CO2) is considered one of the most important trapping mechanisms for geological CO2 storage. Yet, standard procedures for the determination of Sgr-CO2 are missing and Sgr-CO2 has not been determined quantitatively at reservoir until recently. This circumstance introduces uncertainty in the prediction of the nature and capacity of CO2 storage and requires the development of well test procedures. The CO2CRC drilled a dedicated well with perforations in a low salinity aquifer of the Paaratte Formation between 1440 - 1447 m below the surface of the Otway Basin, Australia, with the aim to develop and compare five methods to determine Sgr-CO2 (see also Paterson et al, this volume).

The Petrel Sub-basin Marine Environmental Survey GA-0335, (SOL5463) was undertaken using the RV Solander during May 2012 as part of the Commonwealth Government's National Low Emission Coal Initiative (NLECI). The survey was undertaken as a collaboration between the Australian Institute of Marine Science (AIMS) and GA. The purpose was to acquire geophysical and biophysical data on shallow (less then 100m water depth) seabed environments within two targeted areas in the Petrel Sub-basin to support investigation for CO2 storage potential in these areas. This 10 sample dataset comprises chlorophll abc measurments from surface sediments (0-2 cm) in the Timor Sea.

The CO2CRC has been leading the international development and application of atmospheric techniques for CO2 leak detection and quantification for CCS. CSIRO's atmospheric monitoring program at the CO2CRC Otway Project demonstrated world's leading practice for atmospheric monitoring at geological storage sites. The GA-CO2CRC Ginninderra controlled release facility has enabled development and testing of a new atmospheric tomography approach for accurately quantifying CO2 emissions using atmospheric techniques. A scaled-up version of the technique using an array of more cost effective (but less accurate) sensors was applied at a larger scale at the Otway Stage 2B controlled release. Additional techniques have been developed including data filtering to optimize the detection of emitted gases against the ecosystem background and Bayesian inverse modeling to locate and quantify a source. GA and CSIRO operate a joint baseline atmospheric station in the Bowen Basin and have been independently investigating the sensitivity of CO2 leak detection through coupling of measurements taken in a sub-tropical environment with simulated leakage events. An outcome from this body of work is the importance of good quality, calibrated measurements, a long baseline record and the development and application of techniques using atmospheric models for quantifying gaseous emissions from the ground to the atmosphere. These same measurement requirements and quantification techniques have direct application to fugitive methane emissions from open cut coal mines, coal seam gas, tight gas, and conventional gas emissions. Application is easier for methane: the background signal is lower, sensors are available at affordable cost, and the emissions are measureable now. The Bowen Basin site, for example, is detecting fugitive methane emitted from open cut coal mining activities tens of kilometres away. An example of the sensitivity of atmospheric techniques for the detection of fugitive emissions from a simulated methane source will be presented.

The Petrel Sub-basin Marine Environmental Survey GA-0335, (SOL5463) was undertaken by the RV Solander during May 2012 as part of the Commonwealth Government's National Low Emission Coal Initiative (NLECI). The survey was undertaken as a collaboration between the Australian Institute of Marine Science (AIMS) and GA. The purpose was to acquire geophysical and biophysical data on shallow (less then 100m water depth) seabed environments within two targeted areas in the Petrel Sub-basin to support investigation for CO2 storage potential in these areas. This dataset has analysis of Chlorin and geochemmistry for samples taken on survey.

Geoscience Australia undertook a marine survey of the Leveque Shelf (survey number SOL5754/GA0340), a sub-basin of the Browse Basin, in May 2013. This survey provides seabed and shallow geological information to support an assessment of the CO2 storage potential of the Browse sedimentary basin. The basin, located on the Northwest Shelf, Western Australia, was previously identified by the Carbon Storage Taskforce (2009) as potentially suitable for CO2 storage. The survey was undertaken under the Australian Government's National CO2 Infrastructure Plan (NCIP) to help identify sites suitable for the long term storage of CO2 within reasonable distances of major sources of CO2 emissions. The principal aim of the Leveque Shelf marine survey was to look for evidence of any past or current gas or fluid seepage at the seabed, and to determine whether these features are related to structures (e.g. faults) in the Leveque Shelf area that may extend to the seabed. The survey also mapped seabed habitats and biota to provide information on communities and biophysical features that may be associated with seepage. This research, combined with deeper geological studies undertaken concurrently, addresses key questions on the potential for containment of CO2 in the basin's proposed CO2 storage unit, i.e. the basal sedimentary section (Late Jurassic and Early Cretaceous), and the regional integrity of the Jamieson Formation (the seal unit overlying the main reservoir).

The survey was undertaken as a collaboration between Geoscience Australia and the Australian Institute of Marine Science (AIMS). The purpose was to acquire geophysical and biophysical data on shallow (less than 100 m water depth) seabed environments within two targeted areas in the Petrel Sub-basin to support investigation for CO2 storage potential in these areas. Sub bottom profiler data were acquired using a sparker source and a 24 channel streamer, and processed as shallow, high resolution, multi-channel seismic reflection data.

There are numerous isotopic tracers that have the potential to track the movement of CO2 as it is sequestered underground. Their primary role is in verifying the presence of sequestered CO2. These tracers range from CO2 to 3He to PFT?s to SF6. With such a variety of possible tracers, it is important to identify which tracer(s) are (a) economically viable, (b) can be measured appropriately, (c) fit with the specifics of the geological site, and (d) meet the concerns of the public. Tracers can be used either in a continuous mix with the whole body of sequestered gas as an ownership label or in a pulse to monitor changes in the reservoir characteristics of the body of rock hosting the sequestered gas. Rather than going to the expense of adding a tracer to the stream of sequestered CO2 there may be the opportunity to use natural tracers, such as the very CO2 being injected. In the Weyburn Project, the CO2 injected was isotopically distinct from any CO2 that might have been present in the geological system to which it was being added. The CO2 piped from a gasification plant in North Dakota had an isotopic signature quite depleted in 13C (approx. ?13C -20 to -30?; ref Hirsche et al., 2004). This contrasted with the carbonate minerals and any CO2 present in the hydrocarbon reservoir to which the gas was being sequestered as part of an enhanced oil recovery (EOR) project. Unfortunately, the sequestered CO2 may not be as isotopically different as background sources, for example separating CO2 from natural gas prior to re-injection in the same formation. Costs of tracers per litre can range in orders of magnitude; however the cost should be measured as amount per metric tonne CO2 in order to obtain the true cost. Amounts required tend to be controlled by the background atmospheric presence of any tracer and by the sampling methods and locations. For example, the amount of tracer used to monitor subsurface movement of CO2 from an injection to a monitoring well would potentially be very low if that tracer is not present in deep saline aquifers. However, if shallow water bores or soil or atmospheric level measurements are also being taken, then the presence of the tracer in the soil or atmosphere will strongly control how much additional tracer is required to see changes above background. Addition of 14CO2 to sequestered CO2 may be regarded as a cost effective tracer that will closely mimic CO2. However, it will not advance ahead of the sequestered CO2, it will mask natural differences in 13C/14C variations in the soil and atmosphere, and of course is radiogenic and therefore less favored by the public. By contrast, SF6 (sulphur hexafluoride) is also inexpensive, and has been used in a variety of tracer experiments (Tingey et al., 2000 and references therein). However, SF6 is required in larger volumes (engineering issue for mixing), is increasing in presence in the atmosphere (Maiss and Brenninkmeijer, 1998) and is a highly potent greenhouse gas. As an example of its global warming potential (GWP), 5500 tonnes SF6 is the equivalent of releasing 132 million tons of CO2 (Maiss and Brenninkmeijer, 1998).

The greater Eromanga Basin is an intracratonic Mesozoic basin covering an area approximately 2,000,000 km2 in central and eastern Australia. The greater Eromanga Basin encompasses three correlated basins: the Eromanga Basin (central and western regions), Surat Basin (eastern region) and the Carpentaria Basin (northern region). The greater Eromanga Basin hosts Australia's largest known reserves of groundwater and onshore hydrocarbons and also contains extensive geothermal and uranium systems. The basin has also demonstrated potential as a greenhouse gas sequestration site and will likely play an intrinsic role in securing Australia's energy future. A 3D geological map has been constructed for the greater Eromanga Basin using publicly available datasets. These are principally compiled drilling datasets (i.e. water bores; mineral and petroleum exploration wells) and 1:1,000,000 scale surface geology map of Australia. Geophysical wireline logs, hydrochemistry and radiometrics datasets were also integrated into the 3D geological map